• The Journal of Korean Institute of Next Generation Computing
• /
• v.13 no.6
• /
• pp.7-20
• /
• 2017

The advancement of cloud and big data and the considerable growth of traffic have increased the complexity and problems in the management inefficiency of existing networks. The software-defined networking (SDN) environment has been developed to solve this problem. SDN enables us to control network equipment through programming by separating the transmission and control functions of the equipment. Accordingly, several studies have been conducted to improve the performance of SDN controllers, such as the method of connecting existing legacy equipment with SDN, the packet management method for efficient data communication, and the method of distributing controller load in a centralized architecture. However, there is insufficient research on the control of SDN in terms of the quality of network-using applications. To support the establishment and change of the routing paths that meet the required network service quality, we require a mechanism to identify network requirements based on a contract for application network service quality and to collect information about the current network status and identify the violations of network service quality. This study proposes a method of identifying the quality violations of network paths through ontology to ensure the network service quality of applications and provide efficient services in an SDN environment.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.11 no.5
• /
• pp.7-14
• /
• 2012

We frequently confront with cars interfering into our lane on the ramp. We suffered from serious traffic congestion due to the interfering cars. But the police enforcement has not done actively because it's hard to enforce. In this study, we have evaluated the systems to enforce cutting-in cars through the field test. Generally, the image processing method depends on the weather. To overcome this limitation we proposed a new algorithm combined with section detection method. In the filed test we concluded the results as follows. Whereas the violation detection rate of the general image processing was 58.2%, a new algorithm proposed by this study was 74.5%. And, an error rate enforcing vehicles that do not violate was 0.0%. Also, we can use the existing facilities, such as street light because of compact and lightweight systems which are integrated camera with controller. Therefore, we concluded that it is possible to enforce the interfering Cars using vehicle enforcement systems.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.1
• /
• pp.169-189
• /
• 2015

Detection of anomalous events from video streams is a challenging problem in many video surveillance applications. One such application that has received significant attention from the computer vision community is traffic video surveillance. In this paper, a Lossy Count based Sequential Temporal Pattern mining approach (LC-STP) is proposed for detecting spatio-temporal abnormal events (such as a traffic violation at junction) from sequences of video streams. The proposed approach relies mainly on spatial abstractions of each object, mining frequent temporal patterns in a sequence of video frames to form a regular temporal pattern. In order to detect each object in every frame, the input video is first pre-processed by applying Gaussian Mixture Models. After the detection of foreground objects, the tracking is carried out using block motion estimation by the three-step search method. The primitive events of the object are represented by assigning spatial and temporal symbols corresponding to their location and time information. These primitive events are analyzed to form a temporal pattern in a sequence of video frames, representing temporal relation between various object's primitive events. This is repeated for each window of sequences, and the support for temporal sequence is obtained based on LC-STP to discover regular patterns of normal events. Events deviating from these patterns are identified as anomalies. Unlike the traditional frequent item set mining methods, the proposed method generates maximal frequent patterns without candidate generation. Furthermore, experimental results show that the proposed method performs well and can detect video anomalies in real traffic video data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.10a
• /
• pp.285-288
• /
• 2008

In many intrusion detection applications, n-gram approach has been widely applied. However, n-gram approach has shown a few problems including double counting of features. To address those problems, we applied n-gram augmented Naive Bayes directly to classify intrusive sequences and compared performance with those of Naive Bayes and Support Vector Machines (SVM) with n-gram features by the experiments on host-based intrusion detection benchmark data sets. Experimental results on the University of New Mexico (UNM) benchmark data sets show that the n-gram augmented method, which solves the problem of independence violation that happens when n-gram features are directly applied to Naive Bayes (i.e. Naive Bayes with n-gram features), yields intrusion detectors with higher accuracy than those from Naive Bayes with n-gram features and shows comparable accuracy to those from SVM with n-gram features.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.14 no.1
• /
• pp.112-122
• /
• 2003

Objectives：Considerable data indicate that diminished serotonergic activity is related to aggressive behavior. In order to understand the biological etiology in conduct disorder, we studied the relationships of plasma serotonin and 5-HIAA levels in conduct disorders to measures of aggression, violation of rules and oppositional defiant behavior. Methods：Subjects were selected from inpatients and outpatients department of the Division of Child and Adolescent Psychiatry of Seoul National University Hospital. 41 conduct disorders(18 childhoodonset type, 23 adolescent-onset type) and 23 normal controls were included in this study. For the assessment of aggression, rule violation and oppositional behavior, parents completed the rating scale for conduct disorder and oppositional behavior based on the DSM-IV diagnostic criteria. Plasma serotonin and 5-HIAA levels were determined by HPLC with electrochemical detection. Results：1) Plasma 5-HT and 5-HIAA levels were not significantly different among childhood-onset conduct disorder, adolescent-onset conduct disorder and normal control subjects. 2) No significant correlations were found between plasma 5-HT levels and aggression or rule violation. 3) Plasma 5-HT levels showed significant positive correlations with oppositional behavior both in childhood-onset conduct disorder and adolescent-onset conduct disorder. 4) Age-related changes were not found in plasma 5-HT and 5-HIAA levles. Conclusion：Our findings do not support the hypothesis that dysregulation of serotonergic function may be associated with aggresson. Instead, our data suggest that serotonergic function is more closely related with oppositional behavior than aggression.

• ETRI Journal
• /
• v.32 no.2
• /
• pp.241-247
• /
• 2010

We propose and experimentally demonstrate a service-aware optical transport system. The proposed service-aware optical transport system makes a flow based on service type and priority of traffic. The generated flow is mapped to a corresponding sub-${\lambda}$ for transport over an optical network. Using sub-${\lambda}$ provided by the centralized control plane, we could effectively provide quality-of-service guaranteed Ethernet service and best-effort service simultaneously in a single link. The committed information rate (CIR) traffic and best-effort traffic are assigned to different sub-${\lambda}s$. The bandwidth of the CIR traffic is guaranteed without being affected by violation traffic because the bandwidth is managed per each sub-${\lambda}$. The failure detection time and restoration time from a link failure is measured to be about 60 ${\mu}s$ and 22 ms, respectively, in the ring network. The measured restoration time is much smaller than the 50 ms industry requirement for real-time services. The fast restoration time allows the proposed service-aware optical transport system to offer high availability and reliability which is a requirement for transport networks.

• Journal of Computing Science and Engineering
• /
• v.9 no.4
• /
• pp.190-203
• /
• 2015

Free and open source software (FOSS) has created a large pool of source codes that can be easily copied to create new applications. However, a copy should preserve copyright notice and license of the original file unless the license explicitly permits such a change. Through software evolution, it is challenging to keep original licenses or choose proper licenses. As a result, there are many potential license violations. Despite the fact that violations can have high impact on protecting copyright, identification of violations is highly complex. It relies on manual inspections by experts. However, such inspection cannot be scaled up with open source software released daily worldwide. To make this process scalable, we propose the following two methods: use machine-based algorithms to narrow down the potential violations; and guide non-experts to manually inspect violations. Using the first method, we found 219 projects (76.6%) with potential violations. Using the second method, we show that the accuracy of crowds is comparable to that of experts. Our techniques might help developers identify potential violations, understand the causes, and resolve these violations.

• Journal of Korea Multimedia Society
• /
• v.11 no.8
• /
• pp.1051-1058
• /
• 2008

The advancement of technology for image processing and communications makes it possible for current traffic signal controllers and vehicle detection technology to make both emergency vehicle preemption and transit priority strategies as a part of integrated system. Present]y traffic signal control in crosswalk is controlled by fixed signals. The signal control keeps regular signals traffic even with no traffic, when there is traffic, should wait until the signal is given. Waiting time causes the risk of traffic accidents and traffic congestion in accordance with signal violation. To help reduce the risk of accidents and congestion, this paper explains traffic signal control system for the adaptive priority order so that signal may be preferentially given in accordance with the situation of site through the object detect images.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.1
• /
• pp.396-413
• /
• 2017

Dynamically checking the integrity of software at run-time is always a hot and difficult spot for trusted computing. Control-flow integrity is a basic and important safety property of software integrity. Many classic and emerging security attacks who introduce illegal control-flow to applications can cause unpredictable behaviors of computer-based systems. In this paper, we present a software-based approach to checking violation of control flow integrity at run-time. This paper proposes a high-performance and low-overhead software control flow checking solution, control flow checking at virtual edges (CFCVE). CFCVE assigns a unique signature to each basic block and then inserts a virtual vertex into each edge at compile time. This together with insertion of signature updating instructions and checking instructions into corresponding vertexes and virtual vertexes. Control flow faults can be detected by comparing the run-time signature with the saved one at compile time. Our experimental results show that CFCVE incurs only 10.61% performance overhead on average for several C benchmark programs and the average undetected error rate is only 9.29%. Compared with previous techniques, CFCVE has the characteristics of both high fault coverage and low memory and performance overhead.

• The Korean Society of Law and Medicine
• /
• v.13 no.1
• /
• pp.41-69
• /
• 2012

First introduced in 1977, Korean health care system reached to national coverage in short period of time never seen before in any other countries, and rated as successful system protecting the health of the public at relatively low price. However, despite those positive evaluations, some of fraudulent medical organizations or pharmacies are hindering the sound development of the national health care system with meticulous false billing exaggerating the number of patients or the days of their treatment. To prevent aforementioned nursing home fraud and false billing, the misconduct should be punished as subject to the criminal law and severally punished for fines and payments which far exceed the expected amount of illicit gains as it is basically violation of criminal fraud, other than the forced return of illicit gains based on civil laws. Furthermore, the Health Insurance Review and Assessment Service should strengthen and complement the fraud investigators, the review process, and the professional training to raise the detection rates. It might also want to review ways to implement whistleblower rewarding system and rewards for evidences of healthcare fraud to overcome the limits of external review.